FOOD*2010 Textbook Notes
*Defined words are expressed as bolded, italicized text
Week 2: Chapter 7: Pgs 178-208
7.1 WHAT IS A FOOD ADDITIVE?
Food additive: Substance added to food; a chemical or other substance that becomes a
part of a food product either intentionally or accidentally (mostly intentional), eg. sugar, salt,
corn syrup, baking soda, citric acid and vegetable colouring -> must be government
- From the FFDCA: “any substance the intended use of which results may
reasonably be expected to result, directly or indirectly, in its becoming a component
or otherwise affecting the characteristics of any food (including any substance
intended for use in producing, manufacturing, packing, processing, preparing,
treating, packaging, transporting or holding food; and including any source of
radiation intended for any such use)...
Indirect additives: contaminants - substances that accidentally get into a food product
during production, processing, or packaging
- For the most part, anticipated, with controls to restrict their occurrence to a
Adulteration: deliberate addition of cheap ingredients to a food to make it appear to be of
high quality (intentional food adulteration is illegal in U.S.)
Key uses of food additives:
1. To maintain product consistency (texture and characteristics; via emulsifiers,
stabilizers, thickeners and anticaking agents...)
2. To improve or maintain nutritional value (enrichment, fortification)
3. To maintain palatability and wholesomeness (preservatives)
4. To provide leavening or control acidity/alkalinity (leavening agents; also modification
of pH for flavour, taste and colour)
5. To enhance flavour or impart desired colour (spices, natural/synthetic flavours,
Requirements that guide application of additives:
Efficacy: Food additive must function in food systems in accordance with its stated
function under specific conditions of use.
Must not significantly diminish the nutritional value of the food in which it functions,
nor can it compensate for improper manufacturing practices or inferior products
characteristics in a way that would deceive the customer
Should be detectable by a defined method of analysis Some food additives (considerably, important definitions):
Anticaking and free-flowing agents keep ingredients in a powder form for ease of
incorporation into formulations during manufacturing (eg. silicates and talc).
Antimicrobial agents inhibit bacterial, yeast and mold growth, thus acting as
preservatives (eg. sodium benzoate, fatty acid salts like calcium propionate, sodium
nitrite and nitrates, sodium chloride, sulfur dioxide, sorbic acid, and oxidizing agents
like chlorine, hydrogen peroxide, and iodine).
Colorants or food colours are added to offset colour loss from storage or food
processing, or to correct natural colour variations; certifiable or exempt from
certification; Colour additive certification: via the FDA, assures the safety, quality,
consistency, and strength of a colour additive prior to use. (Includes certified dyes:
water-soluble colorants available in powder, liquid, or paste form; and lakes:
suspensions of organic colorants coated onto metallic salts).
Curing agents for meats contain sodium nitrite, retaining the pink colour of cured
meats and acting as a preservative.
Dough strengtheners improve the machinability of bread dough during processing
(includes emulsifiers such as sodium stearoyl lactylate [SSL], ethoxylated
monoglyceride [EMG] and diacetyl tartaric acid esters of mono- and diglycerides
Emulsifiers keep fat globules dispersed in water or water droplets dispersed in fat
(eg. lecithins, monoglycerides, and diglycerides). Distinct are emulsifying salts:
enhance natural emulsifier activity in food systems (eg. sodium and potassium
phosphates, and citrates).\
Enzymes act as biological catalysts in food (eg. pectinase, glucose oxidase,
Flavourings are added for flavour production or modification (eg. natural essential
oils, synthetic flavourings [often ester compounds] like amyl acetate). Flavour
enhancers: make food taste more delicious (eg. MSG); also flavour potentiator
substances identified chemically as 5’-nucleotides.
Humectants attract water within a food product, which may lower the product’s water
activity; hygroscopic nature of fructose great for use in sweetened baked goods;
(also: polyhydric alcohols or polyols like glycerol/glycerine, sorbitol, mannitol, and
Leavening agents enhance leavening effect, rise, or “oven spring” of dough in baked
products (eg. baking powder [combo of baking soda - sodium bicarbonate - and
cream of tartar - potassium acid tartrate -> with addition of water, produces carbon
dioxide, responsible for leavening effect).
Nutritional additives boost nutrient intake and provide for more balanced diet.
Enrichment: denotes addition of nutrients lost during processing in order to meet a
specific standard for a food (i.e. in bread, flour, and rice). Fortification: addition of
nutrients, either absent or present in insignificant amounts (provides nutrients often
lacking in diet to prevent or correct a particular nutrient deficiency).
Nonnutritive sweeteners provide much greater sweetness intensity per amount
compared to sucrose; small quantity required translates to negligible calorie and
nutrient contribution in a food product (eg. aspartame, acesulfame potassium, and
saccharin) Nutritive sweeteners provide significant calories from carbohydrates in addition to a
level of sweetness intensity (eg. sucrose, fructose, maltose, lactose, polyhydric
alcohols like xylitol and sorbitol, as well as molasses and honey).
Oxidizing agents occur in food mainly as residuals (of chlorine or iodine for example)
from application as sanitizing agents of food processing equipment (will also use
hydrogen peroxide as antimicrobial in dairy with catalase to remove); also act as
bleaching agents to whiten food material like flour (eg. benzoyl peroxide and sodium
hypochlorite used to bleach starch and flour).
pH control agents are acidulants (eg. malic acid, tartaric acid, phosphoric acid, citric
acid, and vinegar) and alkalis or alkaline compounds (eg. sodium hydroxide,
potassium hydroxide - both good in fermented foods to prevent undesirable flavour
development; NaOH can modify functionality of food starches; sodium bicarbonate
also reduces hardness of drinking water and formula water); acidulants can also
enhance flavour and inhibit microorganisms.
Processing aids include acidulants and alkalis, but also buffers and phosphates.
Buffers maintain a constant pH in food by balancing H and OH ions to protect colour,
flavour, and other pH-sensitive characteristics (eg. orthophosphates, citrate, citric
acid, and sodium bicarbonate). Phosphates (eg. polyphosphates) increase water-
holding capacity of meats and stabilize emulsions
Sequestrants/chelating agents combine with metal elements that are active in
oxidation reactions like copper and iron, to form complexes that inhibit development
of off-flavours and odors from oxidation and can protect antioxidants to extend their
effectiveness -> added to metal canned food products (eg. citric acid,
polyphosphates, and ethylenediamine tetra acetate [EDTA])
Stabilizers and thickeners combine with water to increase visco